GlobalEventHandlers.onkeydown
The onkeydown
property of the
GlobalEventHandlers
mixin is an event handler that
processes keydown
events.
The keydown
event fires when the user presses a keyboard key.
Syntax
target.onkeydown = functionRef;
Value
functionRef
is a function name or a function
expression. The function receives a KeyboardEvent
object as its
sole argument.
Example
This example logs the KeyboardEvent.code
value whenever you press down a
key inside the <input>
element.
HTML
<input>
<p id="log"></p>
JavaScript
const input = document.querySelector('input');
const log = document.getElementById('log');
input.onkeydown = logKey;
function logKey(e) {
log.textContent += ` ${e.code}`;
}
Result
Specifications
Specification |
---|
HTML Standard # handler-onkeydown |
Browser compatibility
BCD tables only load in the browser
Compatibility notes
Since Firefox 65, the keyup
and
keydown
events are now fired
during IME composition, to improve cross-browser compatibility for CJKT users
(bug 354358. To
ignore all keydown
events that are part of composition, do something like
this (229 is a special value set for a keyCode
relating to an event that
has been processed by an IME):
eventTarget.addEventListener("keydown", event => {
if (event.isComposing || event.keyCode === 229) {
return;
}
// do something
});
See also
keydown
event- Related event handlers